1. Field of the Invention
The present invention relates to a shifting apparatus for use on a bicycle for shifting a change speed device through a control cable, which shifting apparatus includes a support shaft attachable to a bicycle body, a takeup element rotatably mounted on the support shaft for winding and unwinding the control cable, shift levers for rotating the takeup element, and a lock mechanism for maintaining the takeup element in a selected position.
2. Description of the Related Art
A conventional shifting apparatus for a bicycle as noted above is disclosed in U.S. Pat. No. 5,009,629, for example.
This known apparatus has a support shaft attached at a longitudinally intermediate position thereof to a bicycle body. The support shaft supports shift levers and a lever interlock member mounted on the support shaft from a lower end thereof. The lever interlock member is interlocked to the shift levers through a ratchet type interlocking mechanism to rotate a takeup element. The takeup element and a lock mechanism for setting a position of the takeup element are mounted on the support shaft from an upper end thereof.
In the above construction, the takeup element defines a recess for receiving part of the lock mechanism, but this recess does not accommodate the entire lock mechanism. After locking action, the lock mechanism lies adjacent the upper end of the support shaft which is not covered by the shift levers or other components. Thus, although the entire shifting apparatus is covered by a ease, sand and water tend to enter the ease through an opening inevitably formed in the ease in a range of pivotal movement of the shift levers. Sand or water entering the case and reaching the lock mechanism tends to impair operability of the lock mechanism having balls and a ball bearing.
Further, in the above known construction, the various components are assembled from the opposite ends toward a middle position of the support shaft, not from one end to the other end of the support shaft. This lowers the efficiency of assembly and repair operations.